Rainfall and river flow trends for the Western Cape AUTHORS: Province, South Africa Rakhee Lakhraj-Govender1 Stefan W. Grab2 Climate change has the potential to alter the spatio-temporal distribution of rainfall, subsequently affecting AFFILIATIONS: 1School of Environmental, Water and the supply and demand of water resources. In a water-stressed country such as South Africa, this effect has Earth Sciences, Tshwane University significant consequences. To this end, we investigated annual and winter rainfall and river flow trends for the of Technology, Pretoria, South Africa Western Cape Province over two periods: 1987–2017 and 1960–2017. Annual rainfall for the most recent 2School of Geography, Archaeology and Environmental Studies, University 30-year period shows decreasing trends, with the largest magnitude of decrease at the SA Astronomical of the Witwatersrand, Johannesburg, Observatory rainfall station (-54.38 mm/decade). With the exception of the significant decreasing winter South Africa rainfall trend at Langewens (-34.88 mm/decade), the trends vary between stations for the period 1960– CORRESPONDENCE TO: 2017. For the period 1987–2017, statistically significant decreasing winter trends were found at four of the Rakhee Lakhraj-Govender seven stations, and range from -6.8 mm/decade at Cape Columbine to -34.88 mm/decade at Langewens. Similarly, the magnitudes of decreasing winter river flow at Bree@Ceres and Berg@Franschoek are greater EMAIL:
[email protected] for the more recent 30-year period than for 1960–2017. Correlation coefficients for Vilij@Voeliv rainfall and four river flow stations (Berg@Franschoek, Bree@Ceres, Wit River@Drosterkloof and Little Berg@ DATES: Nieuwkloof) are stronger for shorter periods (i.e.